Monitoring of Epstein–Barr Viral Load in Pediatric Heart and Lung Transplant Recipients by Real-time Polymerase Chain Reaction

Abstract

Elevation in Epstein-Barr virus (EBV) load measured in peripheral blood has been proposed as a marker for development of post-transplant lymphoproliferative disease (PTLD), but there are few published data examining this relationship. We report the longitudinal surveillance of EBV for all recipients of heart (HTx), heart-lung (HLTx) and lung (LTx) transplants at our institution. The study population included all patients transplanted between January 2003 and July 2004. EBV load was serially measured in peripheral blood by real-time polymerase chain reaction (PCR). Results were correlated with recipient pre-transplant EBV status and development of PTLD. Forty-four transplant operations were performed, including 33 HTx, 6 HLTx and 5 LTx. Thirty-two (73%) of the patients were EBV seropositive pre-transplant. Nineteen (44%) pediatric recipients developed EB viremia, including 17 HTx, 1 HLTx and 1 LTx. Eleven (58%) of these patients were EBV seropositive pre-transplant. EBV was first detected at a median of 30.5 days (range 2 to 81) post-transplant. The median peak EBV load in that group was 10,099 copies/ml (range 5,935 to 255,466) whole blood. One patient with cystic fibrosis post-LTx developed PTLD localized in the colon. This patient was EBV seronegative pre-transplant; peak EBV load was 14,513 copies/ml. Acute infectious mononucleosis was seen in 1 case. Positive pre-transplant EBV status did not predict post-transplant EB viremia (positive predictive value 0.03). Contrary to earlier reports, our data demonstrate that a high EBV load does not lead to PTLD early post-transplant. These results do not support the practice of pre-emptively reducing immunosuppression in patients with raised EBV load.